Abstract Maize-bean intercropping is currently gaining popularity among farmers in Germany, although there is hardly any data available on the yield potential under moderate maritime climate conditions in comparison to pure maize cultivation as well as on the choice of the bean cultivar. To assess the agronomic potential of maize-bean intercropping for organic farming, field-experiments over two growing seasons were conducted in Northern Germany (53°46′N, 10°30′E). A split-plot design with two sowing times of the beans as main-plot-factor and different bean species and cultivars (Phaseolus vulgaris, cv.: Cobra, Eva, Tarbais, P. coccineus, cv.: Preisgewinner, Weise Riesen, Vicia faba cv.: Isabell) as subplot-factor was applied. In both years, the average intercropping yield (11 t ha−1 in 2011 and 14 t ha−1 in 2012) of the two sowing dates was comparable to that of maize-control, except for Maize-Eva in 2011. The highest intercropping yields in 2011 were shown by cv. Tarbais and Preisgewinner with bean shares ranging from 34% to 39%. By contrast, the late-sown beans in 2012 had a share of 6–12% only, reflecting the overall higher maize yield level. Compared to maize control, the intercropping with Tarbais and Preisgewinner, which achieved the highest leaf mass scores, led to a significant improvement in crude protein yield by 36% and 18% in 2011, respectively. Earlier ripening bean cultivars (e.g. cv. Eva and Cobra) tend to lose their leaves before harvest. So cultivars with a longer growth period (e.g. cv. Tarbais), similar to maize, should be used to achieve high bean and crude protein yields. Our results demonstrate the importance of cultivar choice for achieving high bean yields that have the potential to improve feed quality. Tarbais and Preisgewinner were the most suitable cultivars for maize-bean intercropping, as they achieved the highest bean yields and improved the crude protein yield in 2011. Even though further optimization is indispensable, we have shown that maize-bean intercropping can fit into organic farming systems under moderate maritime climate.

中文翻译：

---

德国北部的玉米-豆类间作产量与纯青贮玉米相当

摘要 玉米-豆类间作目前在德国农民中越来越受欢迎，尽管与纯玉米种植相比，在温和海洋气候条件下的产量潜力以及豆类品种的选择几乎没有任何可用数据。为了评估玉米-豆类间作在有机农业中的农艺潜力，在德国北部（北纬 53°46'，东经 10°30'）进行了两个生长季节的田间试验。以豆的两个播种时间作为主要小区因素和不同豆种和栽培品种的裂区设计（Phaseolus vulgaris, cv.: Cobra, Eva, Tarbais, P. coccineus, cv.: Preisgewinner, Weise Riesen, Vicia faba cv.: Isabell) 作为子图因子被应用。这两年，两个播期的平均间作产量（2011年11 t ha-1和2012年14 t ha-1）与玉米对照相比，除了2011年的Maize-Eva。2011年间作最高产量为由简历显示。Tarbais 和 Preisgewinner 的豆类份额从 34% 到 39% 不等。相比之下，2012 年晚播的豆类仅占 6-12% 的份额，反映了整体较高的玉米单产水平。与玉米对照相比，与达到最高叶质量分数的 Tarbais 和 Preisgewinner 间作使 2011 年粗蛋白产量分别显着提高了 36% 和 18%。较早成熟的豆类品种（例如 cv. Eva 和 Cobra）在收获前往往会落叶。所以具有较长生长期的栽培品种（例如cv. Tarbais），类似于玉米，应用于实现高豆和粗蛋白产量。我们的结果证明了品种选择对于实现有可能改善饲料质量的高豆产量的重要性。Tarbais 和 Preisgewinner 是最适合玉米 - 豆类间作的品种，因为它们在 2011 年实现了最高的豆产量并提高了粗蛋白产量。 尽管进一步优化是必不可少的，但我们已经证明玉米 - 豆类间作可以适应有机农业温和海洋气候下的系统。